Contact Details

Jussi Heinonen
M.Sc., doctoral candidate

Department of Geosciences and Geography, P.O. Box 64
University of Helsinki
FI-00014 Helsinki
Finland

Phone:
+358-9-191-50802

E-mail:
jussi.s.heinonen@helsinki.fi
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Research interest

My primary research interest are ferropicrites - highly magnesian (MgO > 12 wt. %) and relatively Fe-rich (FeO* > 13 wt. %) volcanic rocks. Phanerozoic (younger than ~540 million years) ferropicrites are found within continental flood basalt (CFB) provinces that represent huge outpourings (up to 2 000 000 cubic kilometers) of magma in relatively short periods of time (~1 to 10 million years) and are often related to continental break-up. My studies have concentrated on ferropicrite dikes that are found in Dronning Maud Land, Antarctica, and are related to the ~180 million-year-old Karoo CFB province. The Karoo CFBs were generated during the initial stages of the break-up of the Gondwana supercontinent which led to the opening of the Indian Ocean and the formation of the continents of South-America, Africa, Antarctica, and Australia.

The emplacements of CFBs have likely had a significant effect on the climate and biosphere and they have been extensively studied in the course of time. Nevertheless, the origins of CFBs are still a matter of considerable debate: a great variety of models have been proposed in order to explain their petrogenesis and geological characteristics. The debate is largely fueled by the lack of knowledge on their parental magmas and mantle sources. This, in turn, stems from the fact that CFBs are fairly evolved (MgO < 10 wt. %) and carry strong lithospheric overprints in their geochemical signatures in general. Ferropicrites, on the other hand, seem to have largely avoided lithospheric contamination. They provide rare and invaluable information on the continental sublithosperic mantle and are thus in key position when unraveling CFB origins.

Project involvement

AMANDA
Anorogenic magmatism in Dronning Maud Land, Antarctica



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